Despite significant findings from large randomized clinical trials related to cardiovascular disease, studies still show significant deficits in the quality of cardiovascular disease care patients receive, suggesting evidence is not consistently translating into care. Health Information Technologies (HIT), such as the electronic health record hold great potential to improve quality of care through improved data management, computerized decision support and population health provisions, such as electronic disease management tools. However, few studies have examined the impact that a comprehensive HIT system has on the delivery of evidence based care. The goal of this study is to evaluate the changes in quality for cardiovascular disease and its associated major risk factors associated with adoption of comprehensive HIT system. We hypothesize that the components of a comprehensive HIT system improve the quality of ambulatory care for ischemic and congestive heart disease by synergistically increasing the delivery of recommended processes of care. The HIT under examination is the VA's Computerized Patient Record System (GPRS); the nations' most widely used HIT system. The study uses a nationwide sample, consisting of the 150 largest ambulatory care clinics in the VA. It uses a retrospective quasi-experimental design which takes advantage of differential diffusion of CPRS amongst ambulatory facilities to address confounding and bias. Primary data collection related to CPRS adoption is currently in its pilot chase.